2 stroke oil (2SO) as an additive to diesel fuel

[CardinalSin]

I can only go by what I have read and remember of the experiences of others.
There are reasons not to use the FD grade. FC is the one for cars with cats or a DPF. FB is fine for the others but FC is a good all round grade. TC-W3 may also be equal or even superior to FC.
Fully synthetic has been found to cause problems. It appears that it doesn't bond with diesel as mineral oil does. It also appears it fails to completely combust in a diesel engine, leaving oil traces in the tailpipe and varnish type deposits in the combustion areas, particularly on the injector nozzles.
So it seems the benefits of using 2SO in a diesel, lubrication and cleaning, are not met with fully synthetic oil. Lubrication may be superior but at a cost.

When I have the time, soon, I will dig through and try to find the posts about fully synthetic 2SO and it's problems. FC over FD too.

[gldgti]

I used 250 ml in the last fill up anyway and the engine is definitely quieter again.

[CardinalSin]

I've had a quick look for reasons not to use fully synthetic or TC-W3 2SO and it was all second hand but I have read the originals earlier.
The only negatives for TC-W3 were based on special additives specific to it's marine applications.
For fully synthetic it was it's inability to bond to mineral diesel fuel which allows it to drop out of solution over time. That might also be the link to incomplete combustion since it's not a fuel suitable for compression ignition as mineral oil is?
I'm negotiating on the purchase of some land and can't focus as I usually can.

[CardinalSin]

Here's another post documenting reduced EGT when using 2SO.

"Here are some actual figures to show that 2 stroke oil added to diesel fuel does have a positive effect.
I run a 2.7 Merc engine. On a regular 300km round trip I have recorded the following twice since adding 2 stroke oil.
I have an EGT digital gauge fitted and the first thing I noticed was the exhaust gas temp was 35 - 40 degrees lower than before
Another positive came from the trip computer which showed an average of 8.3 - 8.5 l/100k without 2 stroke oil; twice now on the same trip with 2 stroke oli added, driving at the same speed on cruise it is returning 7.5 - 7.7 l/100k.
And like most others I have noticed the combustion noise is notieably lower.
I'm happy"

Caravaners Forum • View topic - Adding 2 stroke oil to Diesel Fuel

[twincab]

Is there any evidence that 2so/diesel seperates out like normal 2so/petrol does when left standing for a few weeks.

thanks

[CardinalSin]

Is there any evidence that 2so/diesel seperates out like normal 2so/petrol does when left standing for a few weeks.

thanks

There have been a few tests to see how well it mixes and it appears to bond with diesel, probably because they are so similar both being light oils engineered to combust. I would assume it mixes as well as Caltex and BP diesel do in the same tank.

I always give my chainsaw a good shake up before I start it because i've noticed how 2SO settles out in petrol over time.

[twincab]

Our everyday ride is a 125kw Skoda Superb, but one of our other vehicles is an 05 F350 7.3 which is used for towing duties. Quite often it sits for 2/3 weeks at a time and I was concerned that the 2stroke would seperate out over that time.

[CardinalSin]

Our everyday ride is a 125kw Skoda Superb, but one of our other vehicles is an 05 F350 7.3 which is used for towing duties. Quite often it sits for 2/3 weeks at a time and I was concerned that the 2stroke would seperate out over that time.

I'm sure it wont seperate in diesel but if you're concerned why not mix some in a jar and leave it for a few weeks to see what happens?

Another point might be that in a diesel 2SO is a fuel, unlike when it's used in petrol engines, so the unlikely event of seperation over time would have less if any consequence?

[Transporter]

Our everyday ride is a 125kw Skoda Superb, but one of our other vehicles is an 05 F350 7.3 which is used for towing duties. Quite often it sits for 2/3 weeks at a time and I was concerned that the 2stroke would seperate out over that time.

If your diesel engine seats for 2/3 weeks then you have to also think about the other tasks that proper diesel fuel additives do. Like fighting the bacteria, dispersing water from the fuel system making it safe to pass for the delicate surfaces in the modern diesel fuel systems and much more.

None of this is possible with the 2SO.

[twincab]

Thanks, yes I have been using the Chemtec diesel treatment and thought I'd investigate the 2 stroke option before buying the next bottle.
Think I'll give the Moreys a go this time.

[CardinalSin]

Thanks, yes I have been using the Chemtec diesel treatment and thought I'd investigate the 2 stroke option before buying the next bottle.
Think I'll give the Morleys a go this time.

Dont be put off trying 2 stroke oil.
There's another thread dedicated to the other diesel fuel additives and what they might achieve.

[Preen59]

I'm sure it wont seperate in diesel but if you're concerned why not mix some in a jar and leave it for a few weeks to see what happens?

Another point might be that in a diesel 2SO is a fuel, unlike when it's used in petrol engines, so the unlikely event of seperation over time would have less if any consequence?

As far as I am aware, 2 stroke oil forms an emulsion when mixed with diesel.

[kaanage]

A vegetable based one (ie castor oil) will and maybe some synthetics might but a mineral based 2 stroke oil will fully mix with diesel. I add it to jerry cans and there is no sign of separation after a couple of weeks (they're yellow plastic ones so there's plenty of light when you look in the opening.

If your diesel engine seats for 2/3 weeks then you have to also think about the other tasks that proper diesel fuel additives do. Like fighting the bacteria, dispersing water from the fuel system making it safe to pass for the delicate surfaces in the modern diesel fuel systems and much more.

None of this is possible with the 2SO.

Really? Can you show me the tests where 2 stroke oil has failed in either of these tasks?
Not that I think it would disperse water (which will lessen the lubricating effect in the fuel pump and injectors so the additive had better increase lubricity to offset this) but it could help with the bacteria (would probably be dependant on the exact oil used) although a test would be needed either way.
Gldgti asked for factual proven statements only - I would have no issue if you had worded your last statement as

None of this is has been proven with the 2SO

[Transporter]

Really? Can you show me the tests where 2 stroke oil has failed in either of these tasks?
Not that I think it would disperse water (which will lessen the lubricating effect in the fuel pump and injectors so the additive had better increase lubricity to offset this) but it could help with the bacteria (would probably be dependant on the exact oil used) although a test would be needed either way.
Gldgti asked for factual proven statements only

Now, you're confusing me, "the factual proven statement"? Proven by who?

[kaanage]

As a personal, first hand observation, our 103kW CR MkVI Golf used to produce a light soot layer in the tail pipes (I'd wipe them down every now and then while cleaning the car).

Since adding the TCW-3 2 stroke oil at 200:1 during fillups to this car a couple of months ago, the insides of the tail pipes have remained clean. For what it's worth....

Now, you're confusing me, "the factual proven statement"? Proven by who?

Proven at the least by your own personal observations. Since you never run 2 stroke oil, you can't say definitively what it can and can't do.